const treeData = [
  {
    id: 1,
    name: "技术部",
    children: [
      {
        pid: 1,
        id: 11,
        name: "前端技术部",
        children: [
          { pid: 11, id: 111, name: "小程序技术部" },
          { pid: 11, id: 112, name: "Vue技术部" },
        ],
      },
      { pid: 1, id: 12, name: "Java技术部" },
      { pid: 1, id: 13, name: "Python技术部" },
    ],
  },
  {
    id: 2,
    name: "运营部",
    children: [
      { pid: 2, id: 21, name: "济南运营部" },
      { pid: 2, id: 22, name: "青岛运营部" },
    ],
  },
  { id: 3, name: "行政部" },
];

function list3Tree(list) {
  const arr = [];
  list.forEach((item) => {
    if (item.children) {
      const children = list3Tree(item.children);
      // if (children.length) {
      arr.push(...children);
      // }
    }
    delete item.children;
    arr.push(item);
  });
  return arr;
}
console.log(list3Tree(treeData));
